Comment Re:More to it than that (Score 1) 319
At least some small aircraft have a rotating vane sensor which measures the direction of the airflow in relation to the aircraft, ie. the angle of attack. It may be used to trigger a stall warning if the angle exceeds safe operating limits. I don't know, however, how many larger airliners come with similar equipment - I've seen a picture of one on an A380, at least.